****************************************************** PENGUIN CHARACTERISTICS ****************************************************** ******************** FEATHERS/BLUBBER ******************** __________ QUESTION: How many feathers per square inch do the Emperor Penguins have? What type of feathers are they? How thick is the layer of blubber underneath their feathers? ANSWER from Polly Penhale on February 3, 1995: I'm afraid that I don't know much about the feathers of Emperor Penguins. No one here knows the answer to those questions and we can't find anything in our library. The blubber layer is very thin, only 2-3 mm thick, so the feathers must play an important role in helping protect the birds from the cold temperature. The feathers are so dense that you really can't see their skin underneath. ********* FLIPPERS ********* __________ QUESTION: If you looked at the skeleton of a whale, the bones on one of the flippers look kind of like the bones on a human hand. Is that the same with penguins? ANSWER from Michael Castellini on January 12, 1995: Since whales are mammals like you and me, they have pretty much the same skeleton, except it's made for swimming, of course. They do have "hands" inside their flippers (so do seals). The whales don't have legs though, and those bones are gone. Penguins are birds, however, and their flippers have the same general bone structure as do any birds. The bones are built so that they can "fly" through the water just like flying birds can move through the air. Penguin bones are solid, though, and if you get a chance to look at the flight bones of other birds, you will notice that they are hollow. ********* HEARING ********* __________ QUESTION: How well do penguins hear and where are their ears? ANSWER from Dr. Michael Castellini on February 6, 1995: Penguins, like all birds, can hear quite well. They really do "talk" to each other quite a bit and can be very noisy at times. They have small holes in the side of their heads through which they can hear. What I don't know is how they keep cold water out of their ears when they are diving! *************** INTELLIGENCE *************** __________ QUESTION: How easily are penguins trained; how intelligent are they? ANSWER from Polly Penhale on January 13, 1995 Penguins are not particularly intelligent; they are not like the intelligent birds such as cockatoos or parrots. They have been trained to do relatively simple tasks such as walking in a line or stopping on command. ********** MOLTING? ********** __________ QUESTION: Do penguins shed their skin? ANSWER from Michael Castellini on January 13, 1995: Since penguins are birds, they shed, or "molt" their feathers once a year like most other birds. They will come to the shore and stay on shore while doing this since they must stay dry for their new feathers to come in correctly. They do not shed their skin though. Molting is a very hard thing for the birds to do since they cannot eat and must stay on land. ******* TEETH ******* __________ QUESTION: How many teeth do penguins have? ANSWER from Dr. Michael Castellini on Jan. 13, 1995 Since penguins are birds, they do not have teeth, however they do have a very rough tongue that helps them hold on to slippery fish, squid and other sorts of food. Penguins chicks cannot swim until they have lost their chick down feathers and replaced them with their "adult" feathers. For examples, emperor penguin chicks are hatched in about September and they finally swim away from their rookeries in late December. ************** EYES FREEZE? ************** __________ QUESTION: How do penguin eyes survive the freezing temperature? ANSWER: From Polly Penhale, Program manager in charge of seals, penguins and other NSF biology programs: Penguin eyes do not freeze because, like other mammals eyes, there are numerous blood vessels in the cornea. These vessels may be so small that only the blood plasma passes through and not the red blood cells. This means that you can't see the vessels easily. The blood fluid is warmed so the eye does not freeze. Like many other birds, the Emperor penguin has a transparent membrane (through which the bird can see), called the nictating membrane, which moves back and forth across the eye. This membrane covers the eye while the bird is swimming and provides additional protection from the cold. ANSWER: From Dr. Michael Castellini, Research scientist: seals, penguins and other marine mammals: It turns out that seals have the same problem. The answer is that the eye gets a large amount of blood flow and since the blood is warm, it keeps the eye just warm enough to keep it from freezing. However, you have asked a very good question that many people are working on right now. There is a tremendous amount of heat lost through the eyes as the warm blood keeps the eye from getting too cold. "Heat" pictures of seals in cold water shows that the eye is warm, but loses a lot of heat. The same story works for the penguins and has actually been studied a lot in big fish, like billfish and tuna. They actually have special cells inside their eyes that make heat--we do not know if the same cells exist in marine mammals or penguins. ***************** SENSE OF SMELL ***************** __________ QUESTION: Do penguins have as strong a sense of smell as St. Bernards? ANSWER from Dr. Michael Castellini on January 12, 1995 We don't know, or at least I am not aware of studies that have looked at the abilities of penguins to smell. Unlike the dogs, where smelling is their primary means of sensing the world, the penguins must have good navigation abilities in the water which means good low light vision, and they must be able to find their way over long stretches of sea ice, which means they must be able to navigate by the sun, wind, etc. There is not much to smell in the Antarctic! It is mostly just ice and water! ***************** DIVING ABILITIES ***************** __________ QUESTION: How deep do penguins dive and how long can they stay under the water? ANSWER from Dr. Michael Castellini on January 31, 1995: Since there are quite a few different species of penguins (17), there is also quite a range in their abilities to dive. However, the Emperor penguin is the best diver of them all. We know that it can dive to over 1500 ft deep and that it can dive for over 18 min. However, these dives are not too common--most of the dives are short (about 2-3 minutes) and not as deep--about 200-300 ft. The smallest penguins, the little blues that live in New Zealand and Australia, only dive for less than a minute and usually to less than 100 ft. ****************** FLYING ABILITIES ****************** __________ QUESTION: Can penguins fly? ANSWER from Polly Penhale on January 12, 1995 Whether or not Emperor penguins can fly is a matter of the definition. These birds do not have the ability to sustain flight in the air. If you look at them entering and exiting the water, they may seem to "fly." This is really a giant "leap" in which they can exert great force and propel themselves out of the water onto the ice. ANSWER from Michael Castellini on January 25, 1995 No penguin species is capable of flight in air. They can fly underwater of course, and the way the wings work is just like flying. They are not just paddles, but actually work like wings. So, yes they can fly, just not in the air! ********************* SWIMMING ABILITIES ********************* __________ QUESTION: Do baby penguins have to learn to swim or do they automatically know how? ANSWER from Polly Penhale on January 13, 1995: Emperor penguin chicks first enter the water to swim when they are about six and a half months old. They do not know how to swim and are quite clumsy at first. They still have their down feathers when they first enter the water. These down feathers trap air bubbles so the chicks are too buoyant to swim under the water at first. Once they lose their down feathers, they learn to swim by "practice" and are not taught by adults. ANSWER from Dr. Michael Castellini on January 16, 1995: Both baby penguins and baby seals must learn how to swim. When they first get in the water, they are not very good at it and flop around a lot and don't do a very good job of diving! However, they learn quickly and soon become independent of their parents. In many cases, they must learn by themselves, however, or by watching adults swim! ***************** DOMESTICATION ***************** __________ QUESTION: Have you ever domesticated penguins? If so, how difficult is it? ANSWER from Dr. Michael Castellini on January 16, 1995: Penguins have been kept in zoos for many years, but I am not sure if that is what you would call domestication. Other than that, I don't think that they have been kept for "pet" purposes. They do well in captivity if they can have the right food and be protected from various bird diseases that might get them sick! ******** DIET ******** __________ QUESTION: What do penguins eat and how do they get it? ANSWER from Dr. Michael Castellini on January 16, 1995 Penguins eat mainly small fish and squid. They get this food by diving. Some penguins can dive as deep as 500m to get their food, but others stay near the surface. There are many kinds of penguins and they live in many places, but they all pretty much eat the same thing. They also like to eat krill when in the Antarctic regions! *********************** FOOD: AMOUNT EATEN *********************** __________ QUESTION: How much food do penguins eat a day? ANSWER from Michael Castellini in February 1995 There are many different kinds of penguins and they range in size from very small (about the size of a chicken) to over 70 pounds! So, the amount of food that they eat will be different. However, they usually eat just about one-tenth of their own body weight per day when they are feeding. So, if you have a 30-pound king penguin, it might eat about 3 pounds of fish per day. If you have a 10-pound Adelie, it would eat about 1 pound of fish per day. They also eat squid and krill along with fish. ********************** FOOD: HOW THEY EAT ********************** __________ QUESTION: How do penguins swallow and digest their food without teeth? ANSWER from Dr. Michael Castellini on Jan. 27 1995 Since penguins are birds, they do not have teeth, as you know. So, they capture their fish and squid and krill food in their beaks. Their tongues are very rough with little backward pointing hooks on it and that helps hold their food. They swallow their food pretty fast, so I don't think there is much time for a fish to escape! ************************** EMPEROR PENGUINS: EGGS ************************** __________ QUESTION: Why do emperor penguins lay their eggs in the cold winter months? ANSWER: From Dr. Michael Castellini on February 8, 1995 There is probably not a really good answer. However, we do know that by laying the eggs in the middle of winter, the chicks will be ready to be on their own in the middle of summer. It is probably more important that these chicks have a good chance to survive once they have left their parents in the warm summer than it is for the eggs to be laid when it is cold. The parents can easily keep an egg warm, but they can't do much for the chicks once they leave the nest! ************** LAND OR SEA? ************** __________ QUESTION: Are penguins land or sea animals? ANSWER from Polly Penhale on January 25, 1995: I think of penguins as sea birds, because they are dependent on the ocean for food and spend much of their lives at sea. Penguins come ashore to build nests, lay eggs and raise chicks, but forage for food (either fish or krill, depending on the species and where they live). During breeding season, one adult will sit on the egg or guard the young chick, while the other parent will go off to sea for food for itself and to bring back to the chick. Once the chick gets big, it takes both parents going off for food to keep the chick growing. Finally the chick "fledges," which means it goes off on its own. During the non- breeding time, penguins spend their time at sea or on the sea ice. We really don't know exactly where these birds live while at sea; this is one of the big unanswered questions in penguin studies. ***************** MATURITY RATE ***************** __________ QUESTION: Why do the babies of Adelie penguins mature faster than Emperor babies? ANSWER from Dr. Castellini on January 23, 1995: Maturity rates will be tied in to conditions like climate, stability of the nesting area (i.e., melting ice), food available to the parents, etc. These must all interact to have impacted the maturity rate over the course of evolution, but as to which ones are the most important, I just don't know.